Gazella subgutturosa subgutturosa
General Gestational Data
Twins occur in at least one third of goitered gazelle pregnancies (Walther, 1968; Nowak, 1999). Newborns weigh on average 1,250 g.
Early stages of implantation have not been observed, thus the pregnant uterus to be described presently is of interest.
General Characterization of the Placenta
Details of fetal/maternal barrier
This is a typical epitheliochorial, polycotyledonary placenta with large allantoic cavity. The trophoblast is single-layered and has numerous binucleate cells. Beneath the chorionic plate the trophoblast is more cylindrical. Pigmentations of trophoblast, as seen in many other ungulates, were not present.
The umbilical cord has four large blood vessels and numerous small allantoic vessels, especially distributed around the prominent allantoic duct. The surface of the umbilical cord has numerous foci of squamous metaplasia with keratin production in the mature placenta.
This has not been studied.
Trophoblast external to barrier
No trophoblastic invasion into the endometrium occurs.
There is no subplacenta and no metrial glands develop.
Persian gazelles have the characteristic X-autosome fusion that is shared by many other gazelles. They thus possess 31 chromosomes in the male animal and 30 chromosomes in female (Wurster, 1972; Effron et al., 1976; Hsu & Benirschke, 1977). Hybrids of Persian gazelles with Marica gazelles (Gazella leptoceros marica) occurred in the London Zoo (Gray1972). The X/A fusion is a common feature of many gazelles and antelopes of Africa and it seems to have originated before the invasion of Africa by ungulates from Eurasia. It was studied extensively by Effron et al. (1976). This karyotype of G. s. subgutturosa was confirmed by Benirschke & Kumamoto (1987) who found, in numerous sand gazelles (G. s. marica) studied, varied karyotypes. For females there were 2n=32 and 30, and for males 2n=33 and 31. Hybridization between Persian and sand gazelles was assumed to be the reason for this admixture and it was deemed not to have resulted in subfertility. Similarly, Granjon et al. (1991) assumed hybridization, as they found male sand gazelles from Saudi Arabia with 2n=33 and 2n=31, and females with 2n=32. Nevertheless, our females possessed 2n=31. Kingswood et al. (1994) studied meiosis and karyotypes of Persian gazelles with heterozygosity for the 14/15 autosomal translocation and found that this did not impair fertility. Vassart et al. (1993) found in males from Saudi Arabia and Qatar 33, 32, 31 chromosomes, and in females 32, 31, 30. The process involved the same Robertsonian translocations, with the same autosome. The problem of correct species assignment was again apparent, with the precise place of origin of the population remaining unknown. Other studies exist, as that by Vassart et al. (1995), which also includes protein electrophoretic data. In addition, an important finding is the study of the Chinese G. s. subgutturosa (Orlov, 1987) with identification of 2n=30/31 chromosome numbers. This is essential to know, as no other subspecies exist in that region and hybridization can presumably be excluded.
I am not aware of any studies in this field.
Effron, M., Bogart, M.H., Kumamoto, A.T. and Benirschke, K.: Chromosome studies in the mammalian subfamily Antilopinae. Genetica 46:419-444, 1976.
Granjon, L., Vassart, M., Greth, A. and Cribiu, E.-P.: Genetic study of sand gazelles (Gazella subgutturosa marica) from Saudi Arabia. Chromosomal and isozymic data. Z. Säugetierk. 56:169-176, 191.
A.P.: Mammalian Hybrids. A Check-list with Bibliography. 2nd edition.
Griner, L.A.: Pathology of Zoo Animals. Zoological Society of San Diego, San Diego, California, 1983.
Groves, C.P.: An introduction to the gazelles. Chinkara: Bulletin of the Gazelle Research Group. 1(1):4-16, 1985.
Hsu, T.C. and Benirschke, K.: An Atlas of Mammalian Chromosomes. Vol. 10, Folio 504, 1977.
Kingswood, S.C., Kumamoto, A.T., Sudman, P.D., Fletcher, K.C. and Greenbaum, I.F.: Meiosis in chromosomally heteromorphic goitered gazelle, Gazella subgutturosa (Artiodactyla, Bovidae). Chromosome Research 2:37-46, 1994.
Nowak, R.M.: Walker's Mammals of the World. 6th ed. The Johns Hopkins Press, Baltimore, 1999.
Orlov, in Shi, L.: Recent trends in mammalian cytogenetics in China. La Kromosoma II-45:1458-1467, 1987.
Rostron, J.: A multivariate statistical study the skull measurements of five taxa of gazelles. Biol. J. Linn. Soc. 4:1-14, 1972.
Sempere, A.J., Brown, N., Pereladova, O.B., Bahloul, K., Lacroix, A. and Soldatova, N.: Comparative analysis of reproductive cycles in female Persian gazelle (Gazella subgutturosa subgutturosa) (Central Asia) and sand gazelle (Gazella subgutturosa marica) (Arabian Peninsula). Gen. Comp. Endocrinol. 121:57-65, 2001.
Vassart M, Greth A, Durand V and Cribiu EP. Chromosomal polymorphism in sand gazelles (Gazella subgutturosa marica). J Heredity 84:478-481, 1993.
Vassart, M., Granjon, L. and Greth, A.: Genetic study of Gazella gazella: chromosomal and allozymic data. C. R. Acad. Sc. III 318:27-33, 1995.
Walther, F.: Die Gazellen und ihre Verwandten. In, Gzimeks Tierleben. Volume 13. Kindler-Verlag Zürich, 1968.
Wurster, D.H.: Sex-chromosome translocations and karyotypes in bovid tribes. Cytogenetics 11:197-207, 1972.
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